|
%I #12 Feb 17 2017 15:32:17
%S 0,1,3,4,5,6,8,10,11,12,16,18,22,26,27,29,30,31,32,34,39,40,41,43,44,
%T 45,48,50,51,55,58,60,65,67,69,71,73,78,80,81,83,88,89,92,93,94,96,97,
%U 100,102,103,106,109,110,113,114,115,118,122,125,127,128,129
%N Numbers n such that 90*n + 7 is prime.
%C This sequence was generated by adding 12 Fibonacci-like sequences [See: PROG]. Looking at the format 90n+7 modulo 9 and modulo 10 we see that all entries of A142315 have digital root 7 and last digit 7. (Reverting the process is an application of the Chinese remainder theorem.) The 12 Fibonacci-like sequences are generated (via the p and q values given in the PERL program) from the base p,q pairs 7*91, 19*43, 37*61, 73*79, 11*17, 29*53, 47*71, 83*89, 13*49, 31*67, 23*59, 41*77.
%t Select[Range[0, 200], PrimeQ[90 # + 7] &]
%o (PARI) is(n)=isprime(90*n+7) \\ _Charles R Greathouse IV_, Feb 17 2017
%Y Cf. A181732, A198382, A195993, A196000, A196007, A201739, A201734, A201804, A201816, A201817, A201818, A201820, A201822, A202101, A202104, A202105.
%K nonn,easy
%O 1,3
%A _J. W. Helkenberg_, Dec 11 2011
|
